ABSTRACT This is an application for a K01 Research Career Development Award. The goal of the proposed project is to provide the candidate with advanced skills needed to establish an independent research program examining the relationship between vision loss and cognitive decline in older individuals. To facilitate this long-term goal the candidate will: (1) characterize the longitudinal relationship between objective measures of visual function and cognition in older adults, (2) determine the relationship between vision loss and brain volume and cortical thickness in older adults, and the role brain volume and thickness may play in the vision-cognition relationship, and (3) assess the association between vision loss and participation in cognitively stimulating activities, exploring this participation as a mediator of the vision-cognition relationship. The candidate proposes a comprehensive training plan, combining formal coursework, meetings and tutorials overseen by her mentors, participation in applied training experiences, and involvement in seminars and workshops. Specific training goals include: (1) receive training in the neuropsychological and clinical assessment of older individuals, (2) develop neuroimaging analyses skills, (3) receive training in the neuroscience of vision, (4) gain advanced knowledge of mediation and experimental study design and analyses, and (5) continued training in the responsible conduct of research. The training plan will be executed in coordination with the set of research activities, mentioned above, that are based on preliminary data collected by the applicant. The preliminary data show that reduced visual functioning is associated cross-sectionally with: (1) lower executive function, memory, and language test scores, and (2) reduced gray and white matter volumes, in the visual cortex and frontal lobes . The candidate will expand on these findings, using longitudinal data from participants in the Baltimore Longitudinal Study on Aging (BLSA) who are 60 years and older. The aim of the project is to test the `sensory loss consequence hypothesis', using a multi-domain approach to examine the vision-cognition relationship. The primary hypotheses to be examined are that: (1) reduced visual function is associated with greater declines in executive function, memory, and language test scores, and an increased risk of incident dementia, (2) reduced visual function is associated with reduced brain volume and thickness in regions of interest within the frontal cortex and visual pathways, which mediate the vision-cognition relationship, and (3) age-related vision loss is associated with a reduction in the frequency and variety of participation in cognitively stimulating activities, which also influences the vision-cognition relationship in older adults. Results from this research will be used to develop a subsequent R01 research proposal that will facilitate the candidate's transition to an independent researcher.